AB1650 LATENT TUBERCULOSIS INFECTION IN PATIENTS WITH RHEUMATIC IMMUNE-MEDIATED DISEASES: PREVALENCE AND SCREENING STRATEGY
Authors: C. Lasa, J. S. Osorio Chavez, D. Martínez-López, C. Álvarez-Reguera, V. Portilla, J. M. Cifrián-Martínez, I. Ferraz-Amaro, R. Blanco
Journal: Annals of the Rheumatic Diseases (2023)

<h3>Background</h3> Patients with rheumatic immune-mediated diseases (R-IMID) with latent tuberculosis infection (LTBI) requiring biologic therapy (BT) are at an increased risk of active tuberculosis (TB). The prevalence of LTBI in patients with R-IMID varies depending on geographical location. An accurate diagnosis and prophylactic treatment of LTBI is crucial to reduce the risk of developing TB. No definitive gold standard exists for diagnosing LTBI. Tuberculin skin test (TST) and interferon-γ release assays (IGRAs) are the most used tests. <h3>Objectives</h3> To assess: a) Prevalence of LTBI in patients with (R-IMID), b) determine the importance of using a booster test in negative TST, c) to compare TST with the IGRA test in the detection of LTBI in patients with R-IMID and d) to perform a literature review of prevalence of LTBI in different geographical areas and its relationship with R-IMID. <h3>Methods</h3> Cross-sectional single University hospital study including all patients diagnosed with R-IMID who underwent a TST (±booster) and/or IGRA in a period from 2016 to 2020. If TST was negative, a new TST (Booster) was performed between 1 and 2 weeks after the first TST. Patients were diagnosed with R-IMID by an expert rheumatologist according to well-established ACR/EULAR classification criteria for each R-IMID. LTBI was defined by a positive TST and/or IGRA with no evidence of active TB. Diagnosis with IGRA vs TST was compared using Cohen's kappa coefficient. We performed a literature review in search of previous prevalence studies of LTBI in patients with R-IMID. This search was performed in the month of August 2022. The aim of this review was to compare the prevalence of LTBI in patients with R-IMID in different geographical areas. <h3>Results</h3> We included 1117 patients (741 women/376 men), mean age 53±15 years with LTBI. Overall LTBI prevalence was 31.7 % ranging from 25% in SLE up to 33.3% in BD. Results of prevalence compared to other countries are shown in <b>Table 1</b>. Booster was positive in 66 patients (7.7%) out of 857 patients with a negative simple TST. TST (+booster) was positive in 187 patients (22.9%) out of 817 with a negative or indeterminate IGRA test. IGRA test was positive in 30 (3.8%) out of 793 patients with a negative TST(+booster), as it is represented in <b>Figure 1</b>. Cohen's Kappa coefficient between TST(+booster) and IGRA (QFT-plus), was 0.381. <h3>Conclusion</h3> LTBI is frequent between patients with R-IMID. LTBI screening is important in patients who need to receive BT. This assessment has to be done performing both TST and IGRA as. complementary methods to ensure the detection of all patients with LTBI, since both tests. can have false negative results, especially in patients with R-IMID receiving. immunosuppressive therapy. <h3>REFERENCES:</h3> NIL. <h3>Acknowledgements:</h3> NIL. <h3>Disclosure of Interests</h3> Carmen Lasa: None declared, Joy Selene Osorio Chavez: None declared, David Martínez-López: None declared, Carmen Álvarez-Reguera: None declared, Virginia Portilla: None declared, Jose Manuel Cifrián-Martínez: None declared, Iván Ferraz-Amaro: None declared, Ricardo Blanco Speakers bureau: Ricardo Blanco Speakers bureau: Abbvie, Pfizer, Roche, lilly, Bristol-Myers, Janssen, Galapagos and MSD, Consultant of: Abbvie, Pfizer, Roche, lilly, Bristol-Myers, Janssen and MSD, Grant/research support from: Abbvie, MSD, novartis and Roche.